She also singled out two pieces of evidence that will play a role in the trial – barbecue tongs Sullivan said were used in the murder and contain Pigman’s fingerprint, and the defendant’s journal.

Public Defender Darby Williams in her opening statement hinted at the insanity defense Pigman’s attorneys are expected to mount.

“This is not a whodunit. This case is about one question: Why?” Williams said. “Was this a cold, calculated, pre-meditated killing, or was it something else?”

When Pigman was arrested in the early hours of May 7, 2005, police found him naked, covered in blood, disoriented and occasionally screaming as he paced back and forth atop the roof of a building in San Gabriel.

Pigman’s hands, legs and genital area were covered in blood, according to police investigators.

Yamada’s body was found in the bathroom of her apartment about a block away.

At Pigman’s trial, prosecutors mostly focused on the initial investigative work of law enforcement officials.

Sheriff’s homicide Detective Joseph Sheehy testified he followed a blood trail from the crime scene to the roof where Pigman was found. He also said he found a duffel bag in Yamada’s apartment with Pigman’s passport inside.

A friend of Yamada’s, Misako Saito, testified she walked to a supermarket and a sandwich shop with Pigman and Yamada on the day of her death. Saito said she left the two in Yamada’s apartment that afternoon, and that she observed Pigman smoking marijuana before she left.

Pigman’s father, George Wood Pigman III, a professor of English and executive officer for the humanities at Caltech, was in court Wednesday, as were members of Yamada’s family.